U.S. patent application number 14/960232 was filed with the patent office on 2016-06-30 for outerwear-mounted multi-directional sensor.
This patent application is currently assigned to STAGES PCS, LLC. The applicant listed for this patent is STAGES PCS, LLC. Invention is credited to Benjamin D. Benattar.
Application Number | 20160192066 14/960232 |
Document ID | / |
Family ID | 56165914 |
Filed Date | 2016-06-30 |
United States Patent
Application |
20160192066 |
Kind Code |
A1 |
Benattar; Benjamin D. |
June 30, 2016 |
OUTERWEAR-MOUNTED MULTI-DIRECTIONAL SENSOR
Abstract
A multi-directional sensor may include a microphone array of
three or more microphones mounted on outerwear. The microphone
array may be positioned and configured so that its far field
azimuth sensing range is unobstructed by the outerwear. An
accelerometer may be provided and mounted in a location which is
fixed with respect to the microphones of the microphone array. A
beacon, such as an ultrasonic transmitter or BLE (Bluetooth Low
Energy) transmitter may be associated with or attached to the
outerwear. The microphone array may be utilized with a beam-forming
system in order to determine location of an audio source and a
beam-steering system in order to isolate audio emanating from the
direction of the audio source. The beam-forming system is suitable
for tracking the movement of the audio source in order to inform
the beam-steering system of the direction or location to be
isolated. Because the microphone array will move with a user, a
motion sensor may be provided to reduce the computational resources
required for tracking and isolation by allowing compensation for
change in position and orientation of the user. The beacon will
facilitate location of the wearer.
Inventors: |
Benattar; Benjamin D.;
(Cranbury, NJ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
STAGES PCS, LLC |
Princeton |
NJ |
US |
|
|
Assignee: |
STAGES PCS, LLC
Ewing
NJ
|
Family ID: |
56165914 |
Appl. No.: |
14/960232 |
Filed: |
December 4, 2015 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
14561972 |
Dec 5, 2014 |
|
|
|
14960232 |
|
|
|
|
14827315 |
Aug 15, 2015 |
|
|
|
14561972 |
|
|
|
|
14827316 |
Aug 15, 2015 |
|
|
|
14827315 |
|
|
|
|
14827317 |
Aug 15, 2015 |
|
|
|
14827316 |
|
|
|
|
14827319 |
Aug 15, 2015 |
|
|
|
14827317 |
|
|
|
|
14827320 |
Aug 15, 2015 |
|
|
|
14827319 |
|
|
|
|
14827322 |
Aug 15, 2015 |
|
|
|
14827320 |
|
|
|
|
Current U.S.
Class: |
381/91 ;
367/119 |
Current CPC
Class: |
H04R 2460/07 20130101;
G01P 15/18 20130101; H04R 2201/405 20130101; H04R 1/406 20130101;
H04R 1/1041 20130101; H04R 2430/20 20130101; H04R 2201/023
20130101; H04R 1/1008 20130101; H04R 2201/401 20130101 |
International
Class: |
H04R 1/32 20060101
H04R001/32; H04R 3/00 20060101 H04R003/00; G01P 15/18 20060101
G01P015/18; H04R 1/02 20060101 H04R001/02 |
Claims
1. A body-mounted multi-directional sensor comprising: a base
configured to be worn by a user; a multi-directional acoustic
sensor mounted on said base and wherein said base is outerwear.
2. A body-mounted multi-directional sensor wherein said
multi-directional acoustic sensor further comprised three or more
microphones mounted in a configuration with a first microphone
mounted in a position that is not co-linear with a second
microphone and a third microphone.
3. A body-mounted multi-directional sensor according to claim 2
further comprising a fourth microphone mounted in a location that
is not co-planar with said first microphone, said second microphone
and said third microphone.
4. A multi-directional sensor according to claim 3 wherein said
microphones are mounted on said base in a configuration where, for
every angle of azimuth referenced from said multi-directional
sensor from 0 degrees to 360 degrees, there are at least two
microphones in said array which include the angle of azimuth within
their field of sensitivity and are unobstructed by said base and
user.
5. A multi-directional sensor according to claim 4 wherein said
base is a jacket.
6. A multi-directional sensor according to claim 5 wherein said
first, second and third microphones are mounted on shoulders of
said jacket.
7. A multi-directional sensor according to claim 6, wherein said
fourth microphone is a lateral-mounted microphone positioned at an
elevation generally lower than a shoulder of an intended
wearer.
8. A multi-directional sensor according to claim 3 wherein said
first, second, and third microphones are mounted on a shell.
9. A multi-directional sensor according to claim 2 wherein said
multi-directional acoustic sensor has eight or more
microphones.
10. A multi-directional sensor according to claim 6 further
comprising a beacon transmitter.
11. A multi-directional sensor according to claim 10 wherein said
beacon transmitter is an ultrasound transmitter.
12. A multi-directional sensor according to claim 10 wherein said
beacon transmitter is a radio transmitter.
13. A multi-directional sensor according to claim 12 wherein said
radio transmitter is a Bluetooth low energy transmitter.
14. A multi-directional sensor according to claim 6 further
comprising a motion sensor.
15. A multi-directional sensor according to claim 14 wherein said
motion sensor is a 9-axis sensor.
16. A multi-directional sensor according to claim 14 wherein said
motion sensor is an accelerometer.
17. A multi-directional sensor according to claim 14 wherein said
motion sensor is a gyroscope.
18. A multi-directional sensor according to claim 14 wherein said
motion sensor is a magnetometer.
19. An audio source location tracking and isolation system
comprising: a microphone array having four or more microphones
mounted on a jacket; an accelerometer mounted in a fixed
relationship to said microphone array; a three-dimensional location
processor responsive to said accelerometer; a beam-forming unit
responsive to said microphone array and a location compensation
signal generated by said location processor; and a beam steering
unit responsive to said microphone array and said location
compensation signal generated by said location processor.
20. An audio source location tracking and isolation system
according to claim 19 further comprising an ultrasonic transmitter
connected to said jacket.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of and claims
priority and the benefit of the filing dates of co-pending U.S.
patent application Ser. No. 14/561,972 filed Dec. 5, 2014, U.S.
Pat. No. ______ and its continuation-in-part applications U.S.
patent application Ser. No. 14/827,315 (Attorney Docket Number
111003); Ser. No. 14/827,316 (Attorney Docket Number 111004); Ser.
No. 14/827,317 (Attorney Docket Number 111007); Ser. No. 14/827,319
(Attorney Docket Number 111008); Ser. No. 14/827,320 (Attorney
Docket Number 111009); Ser. No. 14/827,322 (Attorney Docket Number
111010), filed on Aug. 15, 2015, all of which are hereby
incorporated by reference as if fully set forth herein. This
application is related to U.S. patent application Ser. No. ______
(Attorney Docket Number 111012); U.S. patent application Ser. No.
______ (Attorney Docket Number 111013); U.S. patent application
Ser. No. ______ (Attorney Docket Number 111014); U.S. patent
application Ser. No. ______ (Attorney Docket Number 111015); U.S.
patent application Ser. No. ______ (Attorney Docket Number 111016);
U.S. patent application Ser. No. ______ (Attorney Docket Number
111017); U.S. patent application Ser. No. ______ (Attorney Docket
Number 111018); ______; and U.S. patent application Ser. No. ______
(Attorney Docket Number 111019), all filed on even date herewith,
all of which are hereby incorporated by reference as if fully set
forth herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The system relates to a multi-directional acoustic sensor
and more particularly to an outerwear-mounted multi-directional
acoustic sensor.
[0004] 2. Description of the Related Technology
[0005] A microphone is an acoustic-to-electric transducer or sensor
that converts sound into an electrical signal. Personal audio is
typically delivered to a user by headphones. Headphones are a pair
of small speakers that are designed to be held in place close to a
user's ears. They may be electroacoustic transducers which convert
an electrical signal to a corresponding sound in the user's ear.
Headphones are designed to allow a single user to listen to an
audio source privately, in contrast to a loudspeaker which emits
sound into the open air, allowing anyone nearby to listen. Earbuds
or earphones are in-ear versions of headphones.
[0006] A sensitive transducer element of a microphone is called its
element or capsule. Except in thermophone based microphones, sound
is first converted to mechanical motion by means of a diaphragm,
the motion of which is then converted to an electrical signal. A
complete microphone also includes a housing, some means of bringing
the signal from the element to other equipment, and often an
electronic circuit to adapt the output of the capsule to the
equipment being driven. A wireless microphone contains a radio
transmitter.
[0007] The condenser microphone, is also called a capacitor
microphone or electrostatic microphone. Here, the diaphragm acts as
one plate of a capacitor, and the vibrations produce changes in the
distance between the plates.
[0008] A fiber optic microphone converts acoustic waves into
electrical signals by sensing changes in light intensity, instead
of sensing changes in capacitance or magnetic fields as with
conventional microphones. During operation, light from a laser
source travels through an optical fiber to illuminate the surface
of a reflective diaphragm. Sound vibrations of the diaphragm
modulate the intensity of light reflecting off the diaphragm in a
specific direction. The modulated light is then transmitted over a
second optical fiber to a photo detector, which transforms the
intensity-modulated light into analog or digital audio for
transmission or recording. Fiber optic microphones possess high
dynamic and frequency range, similar to the best high fidelity
conventional microphones. Fiber optic microphones do not react to
or influence any electrical, magnetic, electrostatic or radioactive
fields (this is called EMI/RFI immunity). The fiber optic
microphone design is therefore ideal for use in areas where
conventional microphones are ineffective or dangerous, such as
inside industrial turbines or in magnetic resonance imaging (MRI)
equipment environments.
[0009] Fiber optic microphones are robust, resistant to
environmental changes in heat and moisture, and can be produced for
any directionality or impedance matching. The distance between the
microphone's light source and its photo detector may be up to
several kilometers without need for any preamplifier or other
electrical device, making fiber optic microphones suitable for
industrial and surveillance acoustic monitoring. Fiber optic
microphones are suitable for use application areas such as for
infrasound monitoring and noise-canceling.
[0010] U.S. Pat. No. 6,462,808 B2, the disclosure of which is
incorporated by reference herein shows a small optical
microphone/sensor for measuring distances to, and/or physical
properties of, a reflective surface
[0011] The MEMS (MicroElectrical-Mechanical System) microphone is
also called a microphone chip or silicon microphone. A
pressure-sensitive diaphragm is etched directly into a silicon
wafer by MEMS processing techniques, and is usually accompanied
with integrated preamplifier. Most MEMS microphones are variants of
the condenser microphone design. Digital MEMS microphones have
built in analog-to-digital converter (ADC) circuits on the same
CMOS chip making the chip a digital microphone and so more readily
integrated with modern digital products. Major manufacturers
producing MEMS silicon microphones are Wolfson Microelectronics
(WM7xxx), Analog Devices, Akustica (AKU200x), Infineon (SMM310
product), Knowles Electronics, Memstech (MSMx), NXP Semiconductors,
Sonion MEMS, Vesper, AAC Acoustic Technologies, and Omron.
[0012] A microphone's directionality or polar pattern indicates how
sensitive it is to sounds arriving at different angles about its
central axis. The polar pattern represents the locus of points that
produce the same signal level output in the microphone if a given
sound pressure level (SPL) is generated from that point. How the
physical body of the microphone is oriented relative to the
diagrams depends on the microphone design. Large-membrane
microphones are often known as "side fire" or "side address" on the
basis of the sideward orientation of their directionality. Small
diaphragm microphones are commonly known as "end fire" or "top/end
address" on the basis of the orientation of their
directionality.
[0013] Some microphone designs combine several principles in
creating the desired polar pattern. This ranges from shielding
(meaning diffraction/dissipation/absorption) by the housing itself
to electronically combining dual membranes.
[0014] An omni-directional (or non-directional) microphone's
response is generally considered to be a perfect sphere in three
dimensions. In the real world, this is not the case. As with
directional microphones, the polar pattern for an
"omni-directional" microphone is a function of frequency. The body
of the microphone is not infinitely small and, as a consequence, it
tends to get in its own way with respect to sounds arriving from
the rear, causing a slight flattening of the polar response. This
flattening increases as the diameter of the microphone (assuming
it's cylindrical) reaches the wavelength of the frequency in
question.
[0015] A unidirectional microphone is sensitive to sounds from only
one direction.
[0016] A noise-canceling microphone is a highly directional design
intended for noisy environments. One such use is in aircraft
cockpits where they are normally installed as boom microphones on
headsets. Another use is in live event support on loud concert
stages for vocalists involved with live performances. Many
noise-canceling microphones combine signals received from two
diaphragms that are in opposite electrical polarity or are
processed electronically. In dual diaphragm designs, the main
diaphragm is mounted closest to the intended source and the second
is positioned farther away from the source so that it can pick up
environmental sounds to be subtracted from the main diaphragm's
signal. After the two signals have been combined, sounds other than
the intended source are greatly reduced, substantially increasing
intelligibility. Other noise-canceling designs use one diaphragm
that is affected by ports open to the sides and rear of the
microphone.
[0017] Sensitivity indicates how well the microphone converts
acoustic pressure to output voltage. A high sensitivity microphone
creates more voltage and so needs less amplification at the mixer
or recording device. This is a practical concern but is not
directly an indication of the microphone's quality, and in fact the
term sensitivity is something of a misnomer, "transduction gain"
being perhaps more meaningful, (or just "output level") because
true sensitivity is generally set by the noise floor, and too much
"sensitivity" in terms of output level compromises the clipping
level.
[0018] A microphone array is any number of microphones operating in
tandem. Microphone arrays may be used in systems for extracting
voice input from ambient noise (notably telephones, speech
recognition systems, hearing aids), surround sound and related
technologies, binaural recording, locating objects by sound:
acoustic source localization, e.g., military use to locate the
source(s) of artillery fire, aircraft location and tracking.
[0019] Typically, an array is made up of omni-directional
microphones, directional microphones, or a mix of omni-directional
and directional microphones distributed about the perimeter of a
space, linked to a computer that records and interprets the results
into a coherent form. Arrays may also be formed using numbers of
very closely spaced microphones. Given a fixed physical
relationship in space between the different individual microphone
transducer array elements, simultaneous DSP (digital signal
processor) processing of the signals from each of the individual
microphone array elements can create one or more "virtual"
microphones.
[0020] Beamforming or spatial filtering is a signal processing
technique used in sensor arrays for directional signal transmission
or reception. This is achieved by combining elements in a phased
array in such a way that signals at particular angles experience
constructive interference while others experience destructive
interference. A phased array is an array of antennas, microphones
or other sensors in which the relative phases of respective signals
are set in such a way that the effective radiation pattern is
reinforced in a desired direction and suppressed in undesired
directions. The phase relationship may be adjusted for beam
steering. Beamforming can be used at both the transmitting and
receiving ends in order to achieve spatial selectivity. The
improvement compared with omni-directional reception/transmission
is known as the receive/transmit gain (or loss).
[0021] Adaptive beamforming is used to detect and estimate a
signal-of-interest at the output of a sensor array by means of
optimal (e.g., least-squares) spatial filtering and interference
rejection.
[0022] To change the directionality of the array when transmitting,
a beamformer controls the phase and relative amplitude of the
signal at each transmitter, in order to create a pattern of
constructive and destructive interference in the wavefront. When
receiving, information from different sensors is combined in a way
where the expected pattern of radiation is preferentially
observed.
[0023] With narrow-band systems the time delay is equivalent to a
"phase shift", so in the case of a sensor array, each sensor output
is shifted a slightly different amount. This is called a phased
array. A narrow band system, typical of radars or small microphone
arrays, is one where the bandwidth is only a small fraction of the
center frequency. With wide band systems this approximation no
longer holds, which is typical in sonars.
[0024] In the receive beamformer the signal from each sensor may be
amplified by a different "weight." Different weighting patterns
(e.g., Dolph-Chebyshev) can be used to achieve the desired
sensitivity patterns. A main lobe is produced together with nulls
and sidelobes. As well as controlling the main lobe width (the
beam) and the sidelobe levels, the position of a null can be
controlled. This is useful to ignore noise or jammers in one
particular direction, while listening for events in other
directions. A similar result can be obtained on transmission.
[0025] Beamforming techniques can be broadly divided into two
categories: [0026] a. conventional (fixed or switched beam)
beamformers [0027] b. adaptive beamformers or phased array [0028]
i. desired signal maximization mode [0029] ii. interference signal
minimization or cancellation mode
[0030] Conventional beamformers use a fixed set of weightings and
time-delays (or phasings) to combine the signals from the sensors
in the array, primarily using only information about the location
of the sensors in space and the wave directions of interest. In
contrast, adaptive beamforming techniques generally combine this
information with properties of the signals actually received by the
array, typically to improve rejection of unwanted signals from
other directions. This process may be carried out in either the
time or the frequency domain.
[0031] As the name indicates, an adaptive beamformer is able to
automatically adapt its response to different situations. Some
criterion has to be set up to allow the adaption to proceed such as
minimizing the total noise output. Because of the variation of
noise with frequency, in wide band systems it may be desirable to
carry out the process in the frequency domain.
[0032] Beamforming can be computationally intensive.
[0033] Beamforming can be used to try to extract sound sources in a
room, such as multiple speakers in the cocktail party problem. This
requires the locations of the speakers to be known in advance, for
example by using the time of arrival from the sources to mics in
the array, and inferring the locations from the distances.
[0034] A Primer on Digital Beamforming by Toby Haynes, Mar. 26,
1998 http://www.spectrumsignal.com/publications/beamform_primer.pdf
describes beam forming technology.
[0035] According to U.S. Pat. No. 5,581,620, the disclosure of
which is incorporated by reference herein, many communication
systems, such as radar systems, sonar systems and microphone
arrays, use beamforming to enhance the reception of signals. In
contrast to conventional communication systems that do not
discriminate between signals based on the position of the signal
source, beamforming systems are characterized by the capability of
enhancing the reception of signals generated from sources at
specific locations relative to the system.
[0036] Generally, beamforming systems include an array of spatially
distributed sensor elements, such as antennas, sonar phones or
microphones, and a data processing system for combining signals
detected by the array. The data processor combines the signals to
enhance the reception of signals from sources located at select
locations relative to the sensor elements. Essentially, the data
processor "aims" the sensor array in the direction of the signal
source. For example, a linear microphone array uses two or more
microphones to pick up the voice of a talker. Because one
microphone is closer to the talker than the other microphone, there
is a slight time delay between the two microphones. The data
processor adds a time delay to the nearest microphone to coordinate
these two microphones. By compensating for this time delay, the
beamforming system enhances the reception of signals from the
direction of the talker, and essentially aims the microphones at
the talker.
[0037] A beamforming apparatus may connect to an array of sensors,
e.g. microphones that can detect signals generated from a signal
source, such as the voice of a talker. The sensors can be spatially
distributed in a linear, a two-dimensional array or a
three-dimensional array, with a uniform or non-uniform spacing
between sensors. A linear array is useful for an application where
the sensor array is mounted on a wall or a podium talker is then
free to move about a half-plane with an edge defined by the
location of the array. Each sensor detects the voice audio signals
of the talker and generates electrical response signals that
represent these audio signals. An adaptive beamforming apparatus
provides a signal processor that can dynamically determine the
relative time delay between each of the audio signals detected by
the sensors. Further, a signal processor may include a phase
alignment element that uses the time delays to align the frequency
components of the audio signals. The signal processor has a
summation element that adds together the aligned audio signals to
increase the quality of the desired audio source while
simultaneously attenuating sources having different delays relative
to the sensor array. Because the relative time delays for a signal
relate to the position of the signal source relative to the sensor
array, the beamforming apparatus provides, in one aspect, a system
that "aims" the sensor array at the talker to enhance the reception
of signals generated at the location of the talker and to diminish
the energy of signals generated at locations different from that of
the desired talker's location. The practical application of a
linear array is limited to situations which are either in a half
plane or where knowledge of the direction to the source in not
critical. The addition of a third sensor that is not co-linear with
the first two sensors is sufficient to define a planar direction,
also known as azimuth. Three sensors do not provide sufficient
information to determine elevation of a signal source. At least a
fourth sensor, not co-planar with the first three sensors is
required to obtain sufficient information to determine a location
in a three dimensional space.
[0038] Although these systems work well if the position of the
signal source is precisely known, the effectiveness of these
systems drops off dramatically and computational resources required
increases dramatically with slight errors in the estimated a priori
information. For instance, in some systems with source-location
schemes, it has been shown that the data processor must know the
location of the source within a few centimeters to enhance the
reception of signals. Therefore, these systems require precise
knowledge of the position of the source, and precise knowledge of
the position of the sensors. As a consequence, these systems
require both that the sensor elements in the array have a known and
static spatial distribution and that the signal source remains
stationary relative to the sensor array. Furthermore, these
beamforming systems require a first step for determining the talker
position and a second step for aiming the sensor array based on the
expected position of the talker.
[0039] A change in the position and orientation of the sensor can
result in the aforementioned dramatic effects even if the talker is
not moving due to the change in relative position and orientation
due to movement of the arrays. Knowledge of any change in the
location and orientation of the array can compensate for the
increase in computational resources and decrease in effectiveness
of the location determination and sound isolation. An accelerometer
is a device that measures acceleration of an object rigidly inked
to the accelerometer. The acceleration and timing can be used to
determine a change in location and orientation of an object linked
to the accelerometer.
SUMMARY OF THE INVENTION
[0040] It is an object to provide an outerwear-mounted microphone
array.
[0041] It is an object to provide a multi-directional acoustic
sensor able to isolate an audio source in two or three-dimensional
space.
[0042] It is an object to provide an audio sensor array that may be
connected to or integrated with outerwear.
[0043] It is an object to provide a microphone array suitable for
sensing audio information sufficient for determination of the
location of an audio source in a three-dimensional space.
[0044] It is an object to provide an acoustic smart apparel, and
more particularly smart apparel that enhances the use of
directionally discriminating acoustic sensors, directional
recording, ultrasonic location announcements and customized audio.
It is an object to take advantage of the size of outerwear and
geometric configuration to enhance audio capture and customization.
To this end, a sensor array may be connected to or integrated with
outerwear
[0045] The ability to determine distance and direction of an audio
source is related to the accuracy of the sensors, the accuracy of
the processing, and the distance between sensors. A
outerwear-mounted microphone array with a base may be configured to
be worn by a user. Three or more microphones may be mounted on the
base. A first microphone may be mounted in a position that is not
co-linear with a second microphone and a third microphone. A fourth
microphone may be mounted in a location that is not co-planar with
the first microphone, the second microphone and the third
microphone. The base may be outerwear such as a ski jacket, sports
jersey, or other article intended to be worn on a user's torso.
According to a particular embodiment, a fourth microphone may be
mounted on a sleeve. A fifth microphone may be mounted on the
opposite side of the fourth microphone. An accelerometer or other
motion/position sensor such as a gyroscope or magnetometer/compass
(9-axis motion sensor) may be fixed to one or more of the
microphone arrays. It may be affixed to any of the arrays.
Advantageously all of the microphones are in a known relationship
to each other and a motion sensor is also located in a known
relative position or rigidly linked.
[0046] A beam-forming unit may be responsive to the microphone
array. A location compensation signal may be generated by the
location processor, and a beam steering unit may be responsive to
the microphone array and the location compensation signal generated
by the location processor.
[0047] It is an object to work with an audio customization system
to enhance a user's audio environment. One type of enhancement
would allow a user to wear headphones and specify what ambient
audio and source audio will be transmitted to the headphones. Added
enhancements may include the display of an image representing the
location of one or more audio sources referenced to a user, an
audio source, or other location and/or the ability to select one or
more of the sources and to record audio in the direction of the
selected source(s). The system may take advantage of an ability to
identify the location of an acoustic source or a directionally
discriminating acoustic sensor, track an acoustic source, isolate
acoustic signals based on location, source and/or nature of the
acoustic signal, and identify an acoustic source. In addition,
ultrasound may be serve as an acoustic source and communication
medium.
[0048] In order to provide an enhanced audio experience to the
users a source location identification unit may use beamforming in
cooperation with a directionally discriminating acoustic sensor to
identify the location of an audio source. The location of a source
may be accomplished in a wide-scanning mode to identify the
vicinity or general direction of an audio source with respect to a
directionally discriminating acoustic sensor and/or in a narrow
scanning mode to pinpoint an acoustic source. A source location
unit may cooperate with a location table that stores a wide
location of an identified source and a "pinpoint" location. Because
narrow location is computationally intensive, the scope of a narrow
location scan can be limited to the vicinity of sources identified
in a wide location scan. The source location unit may perform the
wide source location scan and the narrow source location scan on
different schedules. The narrow source location scan may be
performed on a more frequent schedule so that audio emanating from
pinpoint locations may be processed for further use.
[0049] The location table may be updated in order to reduce the
processing required to accomplish the pinpoint scans. The location
table may be adjusted by adding a location compensation dependent
on changes in position and orientation of the directionally
discriminating acoustic sensor. In order to adjust the locations
for changes in position and orientation of the sensor array, a
motion sensor, for example, an accelerometer, gyroscope, and/or
manometer, may be rigidly linked to the directionally
discriminating sensor, which may be implemented as a microphone
array. Detected motion of the sensor may be used for motion
compensation. In this way the narrow source location can update the
relative location of sources based on motion of the sensor arrays.
The location table may also be updated on the basis of trajectory.
If over time an audio source presents from different locations
based on motion of the audio source, the differences may be
utilized to predict additional motion and the location table can be
updated on the basis of predicted source location movement. The
location table may track one or more audio sources.
[0050] The locations stored in the location table may be utilized
by a beam-steering unit to focus the sensor array on the locations
and to capture isolated audio from the specified location. The
location table may be utilized to control the schedule of the beam
steering unit on the basis of analysis of the audio from each of
the tracked sources.
[0051] Audio obtained from each tracked source may undergo an
identification process. An identification process is described in
more detail in U.S. patent application Ser. No. 14/827,320 filed
Aug. 15, 2015, the disclosure of which is incorporated herein by
reference. The audio may be processed through a multi-channel
and/or multi-domain process in order to characterize the audio and
a rule set may be applied to the characteristics in order to
ascertain treatment of audio from the particular source.
Multi-channel and multi-domain processing can be computationally
intensive. The result of the multi-channel/multi-domain processing
that most closely fits a rule will indicate the processing. If the
rule indicates that the source is of interest, the pinpoint
location table may be updated and the scanning schedule may be set.
Certain audio may justify higher frequency scanning and capture
than other audio. For example speech or music of interest may be
sampled at a higher frequency than an alarm or a siren of
interest.
[0052] Computational resources may be conserved in some situations.
Some audio information may be more easily characterized and
identified than other audio information. For example, the
aforementioned siren may be relatively uniform and easy to
identify. A gross characterization process may be utilized in order
to identify audio sources which do not require computationally
intense processing of the multi-channel/multi-domain processing
unit. If a gross characterization is performed a ruleset may be
applied to the gross characterization in order to indicate whether
audio from the source should be ignored, should be isolated based
on the gross characterization alone, or should be subjected to the
multi-channel/multi-domain computationally intense processing. The
location table may be updated on the basis of the result of the
gross characterization.
[0053] In this way the computationally intensive functions may be
driven by a location table and the location table settings may
operate to conserve computational resources required. The wide area
source location may be used to add sources to the source location
table at a relatively lower frequency than needed for user
consumption of the audio. Successive processing iterations may
update the location table to reduce the number of sources being
tracked with a pinpoint scan, to predict the location of the
sources to be tracked with a pinpoint scan to reduce the number of
locations that are isolated by the beam-steering unit and reduce
the processing required for the multi-channel/multi-domain
analysis.
[0054] Various objects, features, aspects, and advantages of the
present invention will become more apparent from the following
detailed description of preferred embodiments of the invention,
along with the accompanying drawings in which like numerals
represent like components.
[0055] Moreover, the above objects and advantages of the invention
are illustrative, and not exhaustive, of those that can be achieved
by the invention. Thus, these and other objects and advantages of
the invention will be apparent from the description herein, both as
embodied herein and as modified in view of any variations which
will be apparent to those skilled in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0056] FIG. 1 shows a pair of headphones with an embodiment of a
microphone array.
[0057] FIG. 2 shows a top view of a pair of headphones with a
microphone array.
[0058] FIG. 3 shows a collar-mounted microphone array.
[0059] FIG. 4 illustrates a collar-mounted microphone array
positioned on a user.
[0060] FIG. 5 illustrates a hat-mounted microphone array.
[0061] FIG. 6 shows a further embodiment of a microphone array on a
mounting substrate on a pair of headphones.
[0062] FIG. 7 shows a top view of a mounting substrate.
[0063] FIG. 8 shows a microphone array in an audio source location
and isolation system.
[0064] FIG. 9 shows a front view of a headphone mounted array.
[0065] FIG. 10 shows a jacket-mounted multi-directional array.
[0066] FIG. 11 shows a top view of a jacket-mounted
multi-directional array.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0067] Before the present invention is described in further detail,
it is to be understood that the invention is not limited to the
particular embodiments described, as such may, of course, vary. It
is also to be understood that the terminology used herein is for
the purpose of describing particular embodiments only, and is not
intended to be limiting, since the scope of the present invention
will be limited only by the appended claims.
[0068] Where a range of values is provided, it is understood that
each intervening value, to the tenth of the unit of the lower limit
unless the context clearly dictates otherwise, between the upper
and lower limit of that range and any other stated or intervening
value in that stated range is encompassed within the invention. The
upper and lower limits of these smaller ranges may independently be
included in the smaller ranges is also encompassed within the
invention, subject to any specifically excluded limit in the stated
range. Where the stated range includes one or both of the limits,
ranges excluding either or both of those included limits are also
included in the invention.
[0069] Unless defined otherwise, all technical and scientific terms
used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this invention belongs. Although
any methods and materials similar or equivalent to those described
herein can also be used in the practice or testing of the present
invention, a limited number of the exemplary methods and materials
are described herein.
[0070] It must be noted that as used herein and in the appended
claims, the singular forms "a", "an", and "the" include plural
referents unless the context clearly dictates otherwise. For the
sake of clarity, D/A and A/D conversions and specification of
hardware or software driven processing may not be specified if it
is well understood by those of ordinary skill in the art. The scope
of the disclosures should be understood to include analog
processing and/or digital processing and hardware and/or software
driven components.
[0071] All publications mentioned herein are incorporated herein by
reference to disclose and describe the methods and/or materials in
connection with which the publications are cited. The publications
discussed herein are provided solely for their disclosure prior to
the filing date of the present application. Nothing herein is to be
construed as an admission that the present invention is not
entitled to antedate such publication by virtue of prior invention.
Further, the dates of publication provided may be different from
the actual publication dates, which may need to be independently
confirmed.
[0072] FIG. 1 and FIG. 2 show a pair of headphones with an
integrated microphone array. FIG. 2 shows a top view of a pair of
headphones with an integrated microphone.
[0073] The headphones 101 include a headband 102. The headband 102
forms an arc which when in use sits over the user's head. The
headphones 101 also include ear speakers 103 and 104 connected to
the headband 102. The ear speakers 103 and 104 are colloquially
referred to as "cans." A plurality of microphones 105 are mounted
on the headband 102. There should be at least three microphones, at
least one of the microphones not positioned co-linearly with the
other two microphones to provide signals indicative of at least a
planar direction.
[0074] The microphones in the microphone array are mounted such
that they are not obstructed by the structure of the headphones or
the user's body. Advantageously the microphone array is configured
to have a 360-degree field. An obstruction exists when a point in
the space around the array is not within the field of sensitivity
of at least two microphones in the array. An accelerometer 106 may
be mounted in an ear speaker housing 103.
[0075] FIG. 3 and FIG. 4 show a collar-mounted microphone array
301.
[0076] FIG. 4 illustrates the collar-mounted microphone array 301
positioned on a user. A collar-band 302 adapted to be worn by a
user is shown. The collar-band 302 is a mounting substrate for a
plurality of microphones 303. The microphones 303 may be
circumferentially-distributed on the collar-band 302, and may have
a geometric configuration which may permit the array to have a
360-degree range with no obstructions caused by the collar-band 302
or the user. The collar-band 302 may also include an accelerometer
304 rigidly-mounted on or in the collar band 302.
[0077] FIG. 5 illustrates a hat-mounted microphone array. FIG. 5
illustrates a hat 401. The hat 401 serves as the mounting substrate
for a plurality of microphones 402. The microphones 402 may be
circumferentially-distributed around the hat or on the top of the
hat in a fashion that avoids the hat or any body parts from being a
significant obstruction to the view of the array. The hat 401 may
also carry on accelerometer 404. The accelerometer 404 may be
mounted on a visor 503 of the hat 401. The hat mounted array in
FIG. 5 is suitable for a 360-degree view (azimuth), but not
necessarily elevation.
[0078] FIG. 6 shows a further embodiment of a multi-directional
acoustic sensor. A substrate is adapted to be mounted on a headband
of a set of headphones. The substrate may include three or more
microphones 502 as a microphone array.
[0079] A substrate 203 may be adapted to be mounted on headphone
headband 102. The substrate 203 may be connected to the headband
102 by mounting legs 204 and 205. The mounting legs 204 and 205 may
be resilient in order to absorb vibration induced by the ear
speakers and isolate microphones and an accelerometer in the
array.
[0080] FIG. 7 shows a top view of a mounting substrate 203.
Microphones 502 are mounted on the substrate 203. Advantageously an
accelerometer 501 is also mounted on the substrate 203. The
microphones alternatively may be mounted around the rim 504 of the
substrate 203. According to an embodiment, there may be three
microphones 502 mounted on the substrate 203 where a first
microphones is not co-linear with a second and third microphone.
Line 505 runs through microphone 502B and 502C. As illustrated in
FIG. 7, the location of microphone 502A is not co-linear with the
locations of microphones 502B and 502C as it does not fall on the
line defined by the location of microphones 502B and 502C.
Microphones 502A, 502B and 502C define a plane. A microphone array
of two omni-directional microphones 502B and 502C cannot
distinguish between locations 506 and 507. The addition of a third
microphone 502A may be utilized to differentiate between points
equidistant from line 505 that fall on a line perpendicular to line
505.
[0081] According an advantageous feature, an accelerometer may be
provided in connection with a multi-directional acoustic sensor.
Because the microphone array is configured to be carried by a
person, and because people move, an accelerometer may be used to
ascertain change in position and/or orientation of the microphone
array. It is advantageous that the accelerometer be in a fixed
position relative to the microphones 502 in the array, but need not
be directly mounted on a microphone array substrate. An
accelerometer 304 may be mounted on the collar-band 302 as
illustrated in FIG. 4. An accelerometer may be mounted in a fixed
position on the hat 401 illustrated in FIG. 5, for example, on a
visor 403. The accelerometer may be mounted in any position. The
position 404 of the accelerometer is not critical.
[0082] FIG. 8 shows a microphone array 601 in an audio source
location and isolation system. A beam-forming unit 603 is
responsive to a microphone array 601. The beamforming unit 603 may
process the signals from two or more microphones in the microphone
array 601 to determine the location of an audio source, preferably
the location of the audio source relative to the microphone array.
A location processor 604 may receive location information from the
beam-forming system 603. The location information may be provided
to a beam-steering unit 605 to process the signals obtained from
two or more microphones in the microphone array 601 to isolate
audio emanating from the identified location. A two-dimensional
array is generally suitable for identifying an azimuth direction of
the source. An accelerometer 606 may be mechanically coupled to the
microphone array 601. The accelerometer 606 may provide information
indicative of a change in location or orientation of the microphone
array. This information may be provided to the location processor
604 and utilized to narrow a location search by eliminating change
in the array position and orientation from any adjustment of
beam-forming and beam-scanning direction due to change in location
of the audio source. The use of an accelerometer to ascertain
change in position and/or change in orientation of the microphone
array 601 may reduce the computational resources required for beam
forming and beam scanning.
[0083] FIG. 9 shows a front view of a headphone fitted with a
microphone array suitable for sensing audio information to locate
an audio object in three-dimensional space.
[0084] An azimuthal microphone array 203 may be mounted on
headphones. An additional microphone array 106 may be mounted on
ear speaker 103. Microphone array 106 may include one or more
microphones 108 and may be acoustically and/or vibrationally
isolated by a damping mount from the earphone housing. According to
an embodiment, there may be more than one microphone 108. The
microphones may be dispersed in the same configuration illustrated
in FIG. 7.
[0085] A microphone array 107 may be mounted on ear speaker 104.
Microphone array 107 may have the same configuration as microphone
array 106.
[0086] Microphones may be embedded in the ear speaker housing and
the ear speaker housing may also include noise and vibration
damping insulation to isolate or insulate the microphones 108 from
the acoustic transducer in the ear speakers 103 and 104.
[0087] Three non-co-linear microphones in an array may define a
plane. A microphone array that defines a plane may be utilized for
source detection according to azimuth, but not according to
elevation. At least one additional microphone 108 may be provided
in order to permit source location in three-dimensional space. The
microphone 108 and two other microphones define a second plane that
intersects the first plane. The spatial relationship between the
microphones defining the two planes is a factor, along with
sensitivity, processing accuracy, and distance between the
microphones that contributes to the ability to identify an audio
source in a three-dimensional space.
[0088] In a physical embodiment mounted on headphones, a
configuration with microphones on both ear speaker housings reduces
interference with location finding caused by the structure of the
headphones and the user. Accuracy may be enhanced by providing a
plurality of microphones on or in connection with each ear
speaker.
[0089] FIGS. 10 and 11 show a multi-directional acoustic sensor
integrated into a ski jacket 700. Multi-directional acoustic
sensors may be similarly integrated into other types of outerwear,
particularly activewear. For example, but without limitation, ski
jackets, sports jerseys, jumpsuits, flack jackets, biker jackets,
bomber jackets, dusters, water ski vests, live preservers, or any
other garment to be worn on a torso. The acoustic sensor elements
described herein may be integrated directly into the outer surface
of the outerwear or integrated into a shell worn over the
outerwear.
[0090] The jacket may include a plurality of microphones 701
mounted onto a surface of the jacket 700. Because of the typical
dimensions of outerwear it is possible to position microphone
element 701 at a greater distance from each other than microphone
elements integrated into the headband of a pair of headphones. The
accuracy of the sensing array is dependent in part upon the
distance between the microphone elements, and as such
implementation of a multi-directional acoustic sensor on outerwear
may enhance the accuracy of the directional location and isolation.
Microphone element 701 may be positioned directly on the jacket 700
or microphone elements 701 may be positioned on a base 705 attached
by a fastener 706. The fastener 706 may be hook and loop buttons,
snaps, or other fasteners.
[0091] One or more additional microphone elements 702 may be
attached to the jacket 700 at a position that is not coplanar with
microphone element 701. Advantageously, microphone element 701 may
be positioned on the shoulders or around the collar and neckline
and additional microphones 702 may be positioned at a location
lower than the microphone elements 701. The jacket 700 may also be
provided with a motion sensor 703. The location of the motion
sensor is not critical.
[0092] The jacket 700 may also be provided with an ultrasonic
transmitter 704. The ultrasonic transmitter 704 is useful to
generate an ultrasound signal operating as a beacon. The ultrasound
signal may be inaudible and may also be coded for identification
purposes. In an alternative configuration, an audible acoustic
transmitter or radio frequency transmitter, such as an iBeacon or
other BLE beacon may be used. The transmitter facilitates
identification and location of the protective outerwear.
[0093] The techniques, processes and apparatus described may be
utilized to control operation of any device and conserve use of
resources based on conditions detected or applicable to the
device.
[0094] The invention is described in detail with respect to
preferred embodiments, and it will now be apparent from the
foregoing to those skilled in the art that changes and
modifications may be made without departing from the invention in
its broader aspects, and the invention, therefore, as defined in
the claims, is intended to cover all such changes and modifications
that fall within the true spirit of the invention.
[0095] Thus, specific apparatus for and methods of an
outerwear-mounted multi-directional sensor have been disclosed. It
should be apparent, however, to those skilled in the art that many
more modifications besides those already described are possible
without departing from the inventive concepts herein. The inventive
subject matter, therefore, is not to be restricted except in the
spirit of the disclosure. Moreover, in interpreting the disclosure,
all terms should be interpreted in the broadest possible manner
consistent with the context. In particular, the terms "comprises"
and "comprising" should be interpreted as referring to elements,
components, or steps in a non-exclusive manner, indicating that the
referenced elements, components, or steps may be present, or
utilized, or combined with other elements, components, or steps
that are not expressly referenced.
* * * * *
References